Radiation Protection Glossary

A radiation protection glossary for Radiation Protection Supervisors (RPS), Radiation Protection Advisers (RPA) and anyone else interesting in radiation safety terms and definitions. The glossary is a mixture of health physics , phrases related to radiation protection legislation, transport, practical safety, technical terms and similar.

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For formal advice, see our Radiation Protection Adviser pages. 

Electron volt

The electron volt (eV) is a unit used in Radiation Protection / Health Physics to describe the energy of Ionising Radiation. The value of the eV is derived from the energy required to accelerate an electron through a potential of 1 volt. In more familiar units the eV is approximately equivalent to 1.6 E-19 joules. In everyday use the units of KeV (or MeV) are used as the eV is obviously an extremely small quantity. In training we often say the eV represents the 'punch' that the ionising radiation has to do work (damage) and so can be related to hazard potential.

Two things are infinite: the universe and human stupidity; and I'm not sure about the universe

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